During cleavage, the cell division is very rapid. The daughter cells do not undergo any growth and the cells thus become gradually smaller in volume. Hence

Options

A. the embryo becomes haploid
B. the embryo grows in volume
C. the embryo becomes smaller in volume
D. there is no increase in the volume of the embryo

Answer

### Step-by-Step Solution:

1. **Understanding Cleavage**: Cleavage is the series of rapid cell divisions that occur after fertilization. The zygote, formed by the fusion of male and female gametes, begins to divide without increasing in size.

2. **Cell Division Process**: During cleavage, the zygote undergoes mitotic divisions. Each division results in two daughter cells, which continue to divide rapidly. This process leads to the formation of a multicellular structure.

3. **Volume of Daughter Cells**: Despite the increase in the number of cells, the volume of each daughter cell becomes progressively smaller. This is because the cells are dividing without a corresponding increase in cytoplasmic volume.

4. **Formation of Morula**: As cleavage continues, the zygote transforms into a structure known as the morula, which consists of a specific number of cells (typically 16 to 32 cells). However, the overall size of the embryo does not increase during this stage.

5. **Conclusion**: Since the daughter cells do not grow in size and the overall volume of the embryo remains constant, the correct conclusion is that there is no increase in the volume of the embryo during cleavage.

### Final Answer:
The correct answer is: **There is no increase in volume of the embryo.**

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